Resin-anchored bolt with indentations

ABSTRACT

A strata support system that provides support and balance to a rock mass and reacts to movement of the rock mass. The strata support system includes a borehole that is drilled into a surface of the rock mass. A resin is disposed in the borehole to secure a cable within the borehole. An anchor cable bolt assembly having a plurality of strands that are twisted together to form the cable is inserted into the borehole. At least one of the plurality of strands includes an interrupted outer surface that is defined by a plurality of spaced indentations. The plurality of spaced indentations are formed along the length of the strand and provide for a plurality of surface contours to enhance engagement of the anchor cable bolt with the resin.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional PatentApplication Ser. No. 61/352,611 for a RESIN-ANCHORED BOLT WITHINDENTATIONS, filed on Jun. 8, 2010, which is hereby incorporated byreference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to an anchor cable bolt assembly, and moreparticularly, a strata support system utilizing the anchor cable boltassembly for providing support and balance to a rock mass and reactingto movement of the rock mass in a variety of conditions.

2. Description of the Prior Art

As is well known in the mining industry, there are numerous apparatusand methods used in rock bolting for strata control. An internationallyaccepted method of strata control is full column resin bolting whichprovides rapid and effective strata control at relatively lower costthan traditional external set supports.

Resin-anchored cable bolts are generally defined as “active methods” ofsupport. These active reinforcing methods are intended to react to rockmass movement, develop a restraining force and transfer that force backto the rock mass. This counteracts the driving force and eventuallyresults in a balanced condition when the total mobilized resistancewithin the rock mass is at least equal to the available driving force.

Resin anchored cable bolts can be installed as either passive orpost-tensioned supports. In tensioning applications, standard cableheads, low-profile heads, barrels and wedges, can be used to tension thecable.

One form of an anchored bolt is a cable bolt which is made from smoothcable with cable bulbs, cable buttons, bird-cages, or any other “resininterrupting” device. These “resin interrupting” devices are made in aseparate step during assembly. Typically, a plurality of strands areformed and then twisted to form the cable. Then a separate step, such ascompressing the cable to form a bird cage or bulb, is performed.

SUMMARY OF THE INVENTION

In view of the above, the anchor cable bolt assembly of the presentinvention includes a plurality of strands that are twisted together toform a cable. Each of the of strands that make up the cable have aninterrupted outer surface that is defined by a plurality of spacedindentations fowled along the length of the strands. The spacedindentations disposed in the outer surface of each cable provides forsurface contours that enhance engagement of the anchor cable boltassembly with a resin.

The anchor cable bolt assembly may be used in a strata support systemaccording to the present invention and, is used in the same manner asother resin or grouted bolts. The strata support system includes aborehole that is drilled into a surface of a rock mass. With the anchorcable bolt assembly of the present invention, the borehole to be drilledonly has to be slightly larger than the cable so that the anchor cablebolt assembly can be inserted into the drilled hole and rotated. Afterthe borehole is drilled, a package of grout or resin is inserted intothe borehole and then the anchor cable bolt assembly of the presentinvention, with a plate or other attachments if desired, is insertedinto the borehole and impacted against the package of resin to rupturethe resin package. While the exemplary embodiment discloses the use of aresin package as the source of resin or grout to secure the anchor cablebolt assembly within the borehole, any source of resin or grout known inthe art may be used to secure the anchor cable bolt assembly within theborehole. The anchor cable bolt assembly is then rotated to mix theresin and allow the resin to harden to secure the anchor cable boltassembly within the borehole. It should be noted that the amount ofrotation required and set time for the resin to harden varies based onthe type of grout or resin used. Once hardened, if desired, the anchorcable bolt assembly can be tensioned against the plate or otherattachment by rotating the head portion or barrel with respect to thewedge portion of a tensioning fixture. The anchor cable bolt assembly ofthe present invention can also be used without tensioning if desired.

In general terms, this invention is relatively simple to make andprovides a cost effective anchor cable bolt assembly for strata supportin a variety of conditions. The spaced indentations of the presentinvention provide for sufficient surface contours to engage with theresin, and are much simpler to manufacture than other known anchor cablebolts, such as for example, bulbed or bird-caged cable bolts.

One of the advantages of the anchor cable bolt of the present inventionis the reduced cost in manufacturing because of the elimination of thecompression step which is normally required in making typical cablebolts with bulbs or birdcages. The other advantage is the time-savinginvolved in drilling a smaller hole than that which is typicallyrequired when bulbed or birdcage cable bolts are employed.

These and other features and advantages of this invention will becomemore apparent to those skilled in the art from the detailed descriptionof a preferred embodiment. The drawings that accompany the detaileddescription are described below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is partial perspective view of an anchor cable bolt assemblyaccording to the present invention;

FIG. 2 is a partial side view of a cable used in the anchor cable boltassembly according to the present invention;

FIG. 3 is a partial side view of an exemplary strand that is twistedwith a plurality of like strands to form the cable used in the anchorcable bolt assembly according to the present invention;

FIG. 4 is a side view of a strata support system with a package of resinprior to rupture and the anchor cable bolt assembly in a partiallyinserted position according to the present invention;

FIG. 5 is a side view of a strata support system with a package of resinbeing ruptured and the anchor cable bolt in a fully inserted positionaccording to the present invention;

FIG. 6 is a plane view of a fixture disposed on the end of a cableaccording to the present invention;

FIG. 7 is a perspective view of an exemplary wedge with serrations usedin the fixture according to the subject invention; and

FIG. 8 is a graph showing the anchorage capacity results of an exemplaryembodiment of the present invention.

DETAILED DESCRIPTION OF THE ENABLING EMBODIMENTS

Referring to the Figures, wherein like numerals indicate correspondingparts throughout the several views, an anchor cable bolt assembly 20,and more particularly, a strata support system 22, utilizing the anchorcable bolt assembly 20, for providing support and balance to a rock mass24 and reacting to movement of the rock mass 24 in a variety ofconditions is generally shown.

The strata support system 22, as shown in FIGS. 4 and 5, includes aborehole 26 that is drilled into a rock mass surface 28. The borehole 26is defined by a wall portion 30 within the rock mass 24. A cable 32 ofan anchor cable bolt assembly 20, as discussed below in greater detail,is inserted into the borehole 26 defined in the rock mass 24. A resin 34or grout is disposed in the borehole 26 for securing the cable 32 withinthe borehole 26. The borehole 26 is generally circular and includes abore diameter d_(b). The cable 32 has a cable diameter d_(c) that isless than the bore diameter d_(b). An annulus 36 is defined between thecable 32 and the wall portion 30 of the borehole 26 to allow for theflow of the resin 34 in the annulus 36. The annulus 36 allows the resin34 is engage the portions of the cable 32 that are inserted into theborehole 26 and maximize the surface area of the cable 32 that issecured to the mass.

The present invention provides for an anchor cable bolt assembly 20, asshown in FIG. 1, that includes a plurality of strands 38, 40 that aretwisted together to form the cable 32. As seen in FIG. 1, the cable 32as disclosed has 7 strands, but as will be appreciated by those ofordinary skill in the art, the cable 32 could have more or less strands38, 40, with 5 to 7 strands being typical. Each of the strands 38, 40has a plurality of indentations 42 which extend along the length of thestrand. As shown in FIG. 3, the indentations 42 extend inwardly into theouter surface of the strands 38, 40 that make up the cable 32. In anexemplary embodiment, the indentations 42 may be approximately 0.1inches wide, 0.025 inches long, and 0.002 inches deep, but these valuesare merely exemplary and may vary. While in the exemplary embodiment ofFIGS. 1-5, the indentations 42 are shown to be generally rectangular, itis noted that the indentations 42 can take any form or geometry. Thatis, the spaced indentations 42 can be any shape or geometry that extendsinwardly into the outer surface of the cable 32 to provide for a surfacecontour that enhances engagement of the anchor cable bolt assembly 20with a grout or resin 34.

In the exemplary embodiment, the indentations 42 are formed by runningthe strands 38, 40 through an indenting station in order to dispose thespaced indentations 42 along each of the strands 38, 40. The indentingstation may be any device known in the art for indenting wires. Thespaced indentations 42 result in a plurality of surface contours in theanchor cable bolt assembly 20 that improves or enhances engagement ofthe anchor cable bolt assembly 20 with the grout or resin 34. In theexemplary embodiment, the plurality of strands 38, 40 include aplurality of peripheral strands 38 that are disposed about alongitudinal extending center strand 40. Each of the strands 38, 40 maybe coated or uncoated. The coating may be a galvanized coating or anyother coating known in the art to protect against corrosion and tofacilitate connection to a cable head and wedge assembly 54 or otheranchors as desired. The anchor cable bolt assembly 20 may be used in allcable 32 mining applications to increase anchorage bolt anchorage versussmooth cable, without installing cable bulbs, cable buttons, bird-cages,or any other “resin interrupting” device.

The anchor cable bolt assembly 20 may further include a fixture 46, suchas a tension fixture 46, secured to an end 48 of the cable 32 to tensionthe cable 32 relative to the rock mass 24. A plate 50 may be placedbetween the rock mass 24 and the fixture 46 to assist in tensioning thecable 32 relative to the rock mass 24. The plate 50 may be a flat plate50, domed plate 50, or any other plate 50 known in the art. In theexemplary embodiment, the plate 50 defines a plate opening 52 for thepassage of the cable 32 through the plate 50. The diameter of the plateopening 52 is larger than the cable diameter d_(c) of the cable 32 suchthat the cable 32 can be received through the plate opening 52. Thefixture 46 has a diameter that is greater than the diameter of the plateopening 52 such that fixture 46 cannot pass through the plate opening52. The plate 50 is pushed against the rock mass 24 by the fixture 46which biases the plate 50 towards the rock mass 24 as fixture 46 istightened, thus creating tension in the anchor cable bolt assembly 20 tosecure the anchor cable bolt assembly 20 relative to the rock mass 24.

In the exemplary embodiment, the fixture 46 is a cable head and wedgeassembly 54 that is attached to the end 48 of the cable 32 so that theanchor cable bolt assembly 20 may be tensioned. The cable head and wedgeassembly 54 in the exemplary embodiment is a low profile cable head andwedge assembly 54 which is manufactured by the applicant. It should beappreciated by those of ordinary skill in the art that standard cableheads, low-profile heads, barrels and wedges, and any other coupler ortruss system that is designed for coated or uncoated strands 38, 40could be used. In the exemplary embodiment, the fixture 46 includes awedge portion 56 and a corresponding head portion 58 that work togetherto tension the cable 32 relative to the rock mass 24. The head portion58 includes an internal bore 60 that is tapered. The wedge portion 56includes an outer surface 62 that is tapered complementary to theinternal bore 60. The wedge portion 56 is received in the internal bore60 of the head portion 58 to tension the cable 32 relative to the rockmass 24.

The wedge portion 56 engages the cable 32 and secures the cable 32within the head portion 58 as wedge portion 56 pulled into thecorresponding head portion 58. As shown in FIG. 7, the wedge portion 56has an inner surface 70 that is serrated with a plurality of knurls orserrations 72 for improved engagement with the anchor cable boltassembly 20. That is, the serrations 72 allow the wedge portion 56 to“bite” into the cable 32 of the anchor cable bolt assembly 20. The wedgeportion 56 fits concentrically around the cable 32 of the anchor cablebolt assembly 20, and also nests concentrically within the internallytapered head portion 58. That is, the end 48 of the cable 32 is setbetween the wedges 44 and pulled into the cable head portion 58 atspecified forces to tension and hold the cable 32. The specified forcesvary based on the materials used and the tension desired, and as such,these specified forces are determined by the user.

The head portion 58 may include a hexagonal shaped outer surface 64 thatreceives a driving mechanism to rotate the head portion 58 and tensionthe cable 32. Although the collar is shown as a hexagonal head,obviously a square head or any other shaped head that accepts a mineroof bolt driver mechanism and boom should function adequately for theintended purpose.

The wedge portion 56 may include a plurality of wedges 44 that aredisposed about and secured to the cable 32 portion. The wedge portion 56is disclosed as a two piece wedge 44 set, but could be a three piecewedge 44 set if desired. When positioned within the head portion 58 andaround the cable 32, the individual wedges 44 define a diametric spacebetween each of the wedges 44 to enable the wedges 44 to be urgedtogether tightly when pressed against the cable 32.

Creating this cable head and wedge assembly 54 can be accomplished bypressing the wedges 44 and cable 32 into the head portion 58 as theanchor cable bolt assembly 20 is manufactured. In addition, the cablehead and wedge assembly 54 can be created on site by cutting the cable32 to the desired length, assembling the cable 32, wedges 44, and headportion 58, and then tensioning the cable 32 against the head portion58, or otherwise pressing the wedges 44 and cable 32 into the headportion 58.

A cap (not shown) may be used to secure the plurality of strands 38, 40at the inserted end 66 of the anchor cable bolt assembly 20. Theinserted end 66 of the anchor cable bolt assembly 20 is the end of thecable 32 that is initially fed into the borehole 26. The cap may be anycap known in the art. The cap may extend outwardly from the inserted end66 of the anchor cable bolt assembly 20 and assists in rupturing thepackage of resin 34. In addition, the cap may include at least one wingthat extends radially from the cap towards the wall portion 30 of theborehole 26 to mix the resin 34 when the cable 32 bolt assembly isrotated.

The subject invention further provides for a method of forming a stratasupport system 22. The method begins by forming the interrupted outersurface 68 on at least one of the plurality of strands 38, 40. While inthe exemplary embodiment, each of the plurality of strands 38, 40includes the interrupted outer surface 68, it is not necessary that eachstrand 38,40 has the plurality of spaced indentations 42 that foil theinterrupted outer surface 68. The strands 38, 40 may include a pluralityof peripheral strands 38 that are twisted about a center strand 40. Inthe exemplary embodiment, each of the peripheral strands 38 are passedthrough an indenting station in order to dispose the spaced indentations42 along each of the peripheral strands 38. After the strands 38, 40have been formed, they are twisted together to form the cable 32.

The anchor cable bolt assembly 20 of the present invention is made in amanner similar to the method used to make typical anchor cable boltassemblies 20 such as bulbed cable bolts, except for two importantdifferences. First, when the individual strands 38, 40 are formed, eachstrand is passed through an indenting station which forms spacedindentations 42 along the length of the strands 38, 40. Second, duringassembly, the step of compressing the cable 32 to form the bulb iseliminated.

A borehole 26 that receives the cable 32 is drilled into the rock mass24 to a desired bore diameter d_(b) and depth. With the anchor cablebolt assembly 20 of the present invention, the hole to be drilled onlyhas to be slightly larger than the cable 32 so that the anchor cablebolt assembly 20 can be inserted into the drilled hole and rotated.Prior to the cable 32 being inserted into the borehole 26, a package orpouch of grout or resin 34 is placed into the borehole 26. In theexemplary embodiment, the package of resin 34 is inserted all the way tothe top of the borehole 26 before the package of resin 34 is broken. Thecable 32 is then inserted into the borehole 26 and is used to push thepackage of resin 34 towards the top of the borehole 26. Once the packageof resin 34 engages the top of the borehole 26 the cable 32 is continuedto be urged upwardly to rupture the package of resin 34. The resin 34flows downwardly through the annulus 36 to surround the cable 32. Thecable 32 is rotated to mix the resin 34. It should be noted that theamount of rotation required and set time for the grout or resin 34 toharden varies based on the type of grout or resin 34 used. Oncehardened, if desired, the anchor cable bolt assembly 20 can be tensionedagainst the plate 50 or other attachment by rotating the head portion 58or barrel with respect to the wedge portion 56 of the tensioning fixture46. As a result of the tensioning, support and balance are provided tothe rock mass 24 via the anchor cable bolt assembly 20. The anchor cablebolt assembly 20 of the present invention can also be used withouttensioning if desired.

While the exemplary embodiment discloses the use of a package of resin34 as the source of grout or resin 34 to secure the anchor cable boltassembly 20 within the borehole 26, any source of grout, resin 34, orother organic or chemical based anchorage formulation known in the artmay be used to secure the anchor cable bolt assembly 20 within theborehole 26. For example, the grout or resin 34 could additionallyinclude, but is not limited, to a pumpable grout or resin 34, which ispumped into the annulus 36 that surrounds the cable 32 after the cable32 has been inserted into the borehole 26.

The anchor cable bolt assembly 20 of the present invention can beinstalled as either passive or post-tensioned supports, and with anyresin type that will provide adequate anchorage to allow for ultimateload capacity, such as for example, polyester, cementious, polyurethane, etc. Additionally, the anchor cable bolt assembly 20, if usedas an active support (either vertical, horizontal, or in a trusssystem), can be tensioned using any of the modes or methods also used totension smooth (coated or uncoated) strands. The combination of theanchor cable bolt assembly 20 and resin 34 of the present inventionprovides a stiffer support with less deflection and deformation as loadincreases.

The strata support system 22 utilizing the anchor cable bolt assembly 20of the present invention, has been found through testing to exhibitsuperior anchorage and performance in mining applications. Laboratorytesting has indicated that the anchor cable bolt assembly 20 of thepresent invention is capable of meeting or exceeding the ASTM tensilerequirements. The strands 38, 40 having indentations 42 and theinteraction the fixture 46 was confirmed to have no adverse reaction tocurrent manufacturing methods.

In addition, field tests have been conducted to confirm anchoragecapacity when used with polyester resin 34 products. Ten (10) foot longcables 32 were fitted with a traditional head portion 58 and wedgeportion 56. The anchor cable bolt assembly 20 were installed in a 1-inchdiameter borehole 26 using a traditional A23 5′ equivalent cartridge.The resin 34 was allowed to cure and pull-tests were performed recordingthe applied load and displacement. The results were compared with anchorcable bolt assembly 20 that were manufactured with three; 1-inch bulbslocated 10, 22, and 33-inches from the bolt end 48. FIG. 8 shows theanchorage capacity test results for the anchor cable bolt assembly 20 ofthe present invention. All of the tests indicated that the cable 32 ofthe present invention was brought well into yield and anchorage wasadequate for the application, see FIG. 8.

The results were compared to the traditionally bulbed cables 32 (usedfor anchoring in polyester resin 34), installed in the same geologicalstructure. The data indicated that the anchor cable bolt assembly 20demonstrated higher system stiffness, which is a support systemadvantage.

It will be appreciated by those of ordinary skill in the art that thecable 32 can work on any diameter strand and increase anchorage, ascompared to smooth cable, in traditional mining applications withpolyester resin 34 or other chemical anchorage formulations.

The spaced indentations 42 of the present invention do not adverselyaffect the tensile strength or yield capacity of the anchor cable boltassembly 20. The cable 32 results in higher bolting system stiffnesswhen installed in conjunction with the proper borehole 26 diameter andpolyester resin 34 and can be used with standard head portions 58,low-profile heads, barrels and wedges 44, and any other coupler or trusssystem that is designed for coated or uncoated (smooth bright orgalvanized) strand.

The foregoing invention has been described in accordance with therelevant legal standards, thus the description is exemplary rather thanlimiting in nature. Variations and modifications to the disclosedembodiment may become apparent to those skilled in the art and do comewithin the scope of the invention. Accordingly, the scope of legalprotection afforded this invention can only be determined by studyingthe following claims.

1. An anchor cable bolt assembly for providing support and balance to arock mass and reacting to movement of the rock mass comprising: aplurality of strands twisted together to faun a cable, at least one ofsaid plurality of strands having an interrupted outer surface defined bya plurality of spaced indentations formed along a length of said atleast one strand, and wherein said plurality of spaced indentationsprovide for a plurality of surface contours for engagement with a resin.2. The anchor cable bolt assembly as set forth in claim l furtherincluding a fixture secured to an end of said cable for tensioning saidcable relative to the rock mass.
 3. The anchor cable bolt assembly asset forth in claim 2 further including a plate for placement between therock mass and said fixture for tensioning said cable relative to therock mass, said plate defining a plate opening for the passage of saidcable through said plate.
 4. The anchor cable bolt assembly as set forthin claim 2 wherein said fixture includes a wedge portion and acorresponding head portion, wherein said wedge portion engages saidcable and secures said cable within said head portion as wedge portionengages said corresponding head portion for tensioning said cable. 5.The anchor cable bolt assembly as set forth in claim 4 wherein said headportion includes an internal bore that is tapered, and said wedgeportion includes an outer surface that is tapered and complementary tosaid internal bore for being received in said internal bore of said headportion for tensioning said cable relative to the rock mass.
 6. Theanchor cable assembly as set forth in claim 4 wherein said head portionincludes a hexagonal shaped outer surface for receiving a drivingmechanism to rotate said head portion and tension said cable.
 7. Theanchor cable assembly as set forth in claim 4 wherein said wedge portionincludes a plurality of wedges disposed about said cable for engagementwith said cable.
 8. The anchor cable bolt assembly as set forth in claim7 wherein at least one of said wedges includes an inner surface having aplurality of serrations for securing said at least one wedge to saidcable.
 9. The anchor cable bolt assembly as set forth in claim 1 whereinsaid plurality of strands include a longitudinally extending centerstrand and a plurality of peripheral strands spirally wrapped aroundsaid center strand.
 10. The anchor cable bolt assembly as set forth inclaim 9 wherein each of said plurality of peripheral strands includes aninterrupted outer surface defined by said plurality of spacedindentations formed along the length of each of said plurality ofperipheral strands.
 11. The anchor cable bolt assembly as set forth inclaim 1 wherein each of said plurality of strands are coated.
 12. Theanchor cable bolt assembly as set forth in claim 1 wherein each of saidplurality of strands are uncoated.
 13. A strata support system forproviding support and balance to a rock mass and reacting to movement ofthe rock mass comprising: a borehole having a bore diameter and beingdrilled into a rock mass surface; a plurality of strands, with each ofsaid plurality of strands having a length and being twisted together toform a cable having a cable diameter and capable of being inserted intosaid borehole; and a resin disposed in said borehole for securing saidcable within said borehole; wherein at least one of said plurality ofstrands includes an interrupted outer surface defined by a plurality ofspaced indentations formed along the length of said at least one strandfor providing a plurality of surface contours to engage with said resin.14. The strata support system as set forth in claim 13 further includinga fixture secured to an end of said cable for tensioning said cablerelative to said rock mass.
 15. The strata support system as set forthin claim 14 further including a plate for placement between said rockmass and said fixture to tension said cable relative to said rock mass,said plate defining a plate opening for the passage of said cablethrough said plate.
 16. The strata support system as set forth in claim14 wherein said fixture includes a wedge portion and a correspondinghead portion, wherein said wedge portion engages said cable and securessaid cable within said head portion as wedge portion engages saidcorresponding head portion for tensioning said cable.
 17. The stratasupport system as set forth in claim 16 wherein said head portionincludes an internal bore is tapered, and said wedge portion includes anouter diameter that is tapered and complementary to said internal borefor being received in said internal bore of said head portion fortensioning said cable.
 18. The strata support system as set forth inclaim 16 wherein said head portion includes a hexagonal shaped outersurface for receiving a driving mechanism to rotate said head portionand tension said cable.
 19. The strata support system as set forth inclaim 16 wherein said wedge portion includes a plurality of wedgesdisposed about said cable for engagement with said cable.
 20. The stratasupport system as set forth in claim 19 wherein at least one of saidwedges includes an inner surface having a plurality of serrations forsecuring said at least one wedge to said cable.
 21. The strata supportsystem as set forth in claim 13 wherein said plurality of strandsinclude a longitudinally extending center strand and a plurality ofperipheral strands spirally wrapped around said center strand.
 22. Theanchor cable bolt assembly as set forth in claim 21 wherein each of saidplurality of peripheral strands includes an interrupted outer surfacedefined by said plurality of spaced indentations formed along the lengthof each of said plurality of peripheral strands.
 23. The strata supportsystem as set forth in claim 13 wherein said cable diameter is less thansaid bore diameter.
 24. The strata support system as set forth in claim23 wherein said borehole is defined by a wall portion within said rockmass, and further includes an annulus defined between said cable andsaid wall portion of said borehole for the flow of said resin in saidannulus.
 25. A method of forming a strata support system for providingsupport and balance to a rock mass and reacting to movement of the rockmass, comprising the steps of: forming an interrupted outer surface onat least one of a plurality of strands; twisting together the pluralityof strands to form a cable; drilling a borehole into a surface of a rockmass for receiving the cable; disposing a resin in the borehole forsecuring the cable within the borehole; and inserting the cable into theborehole; wherein the plurality of indentations provide for a pluralityof surface contours for engagement with the resin.
 26. The method offorming the strata support system as set forth in claim 25 wherein theforming step is further defined as disposing a plurality of spacedindentations along a length of the at least one strand.
 27. The methodof forming the strata support system as set forth in claim 25 whereinthe forming step is further defined as passing the at least one strandthrough an indenting station to dispose a plurality of spacedindentations along a length of the at least one strand.
 28. The methodof forming the strata support system as set forth in claim 25 furtherincluding the step of tensioning the cable relative to the rock mass.29. The method of forming the strata support system as set forth inclaim 25 wherein the forming step is further defined as forming aninterrupted outer surface on a plurality of strands.